Requirements

A semi-modern tar in $PATH. It should accept the "xf -" switches to mean "extract the tar file which is offered on stdin". It should also allow extended GNU tarfiles, as some eggs include filenames longer than 64 characters. Most tar implementations do.

Documentation

This egg installs a small program called henrietta-cache which reads a file containing egg-to-URI mappings. These URIs are expected to resolve to a so-called "release-info" file, which provides further instructions on how to fetch actual releases of the egg.

These releases are downloaded into a caching directory, which can then be served by henrietta for use by chicken-install.

The CACHEDIR points at the directory in which to place the cached files. It defaults to "cache". It will automatically create a subdirectory for each egg in the list and create a subdirectory called "tags" underneath those, in which it creates one directory for each release. This structure is used because it is expected by henrietta, and may change in the future.

The EGGLIST points to a file containing the list of eggs to fetch. It may be either a filename or an HTTP(S) URI.

The INITFILE is a file which will be loaded before starting the download process. This can be used to set handlers on the hooks, as documented below.

Hooks

This is a hook you can register to run some code whenever a full release of an egg has been successfully downloaded.

SUCCESS-HOOK is a procedure of two arguments: the egg name and the release version (both strings).

[parameter](download-release-error-hook [ERROR-HOOK])

This is a hook you can register to run some code whenever a full release of an egg has failed to download.

ERROR-HOOK is a procedure of three arguments: the egg name, the release version and the error message on the exception that was thrown when the failure happened (all three are strings).

[parameter](download-release-info-file-error-hook [ERROR-HOOK])

This is a hook you can register to run some code whenever the download of the release-info file of an egg failed.

ERROR-HOOK is a procedure of three arguments: the egg name, the URI-string of the release-info file's location and the error message on the exception that was thrown when the failure happend (all three are strings).

Changelog

0.4 - Use tar instead of pax, as it won't accept extended GNU tar files (and ustar archives have crippling limitations on maximum file length). Thanks to Alaric Snell-Pym for pointing out this problem. Make downloads more robust against failure by downloading/extracting to a tempdir and moving only when everything is alright.

Author

Repository

License

Copyright (c) 2011-2013, Peter Bex
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
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documentation and/or other materials provided with the distribution.
3. The name of the authors may not be used to endorse or promote products
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